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Resonance saturation for four-nucleon operators

Evgeny Epelbaum·Ulf-G. Meißner·Walter Glöckle·Charlotte Elster
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Abstract

In the modern description of nuclear forces based on chiral effective field theory, four-nucleon operators with unknown coupling constants appear. These couplings can be fixed by a fit to the low partial waves of neutron-proton scattering. We show that the so determined numerical values can be understood on the basis of phenomenological one-boson-exchange models. We also extract these values from various modern high accuracy nucleon-nucleon potentials and demonstrate their consistency and remarkable agreement with the values in the chiral effective field theory approach. This paves the way for estimating the low-energy constants of operators with more nucleon fields and/or external probes.

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Evgeny Epelbaum, Ulf-G. Meißner, Walter Glöckle, Charlotte Elster. 2001-06-05. Resonance saturation for four-nucleon operators. https://doi.org/10.1103/physrevc.65.044001

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